Extracorporeal Membrane Oxygenation (ECMO) is a temporary procedure for treating human neonates who have reversible, severely impaired lung function refractory to conventional treatment. During ECMO deoxygenated blood is shunted from the hypoxic infant to an external oxygenating membrane and returned to the arterial circulation allowing the infant's lungs to recover during the by-pass. The right internal jugular vein (RUV) and the right common carotid artery (RCCA) are permanently sacrificed because they are cannulated to gain access to the right atrium and the aorta during ECMO. Although focal brain damage directly related to ligation of the RCCA or RUV has not been consistently noted in surviving neonates who have been treated with ECMO at Thomas Jefferson University Hospital, abnormalities in EEG tracings cranial ultrasound images and CT scans have been frequently noted Cerebral palsy or developmental delay or both have also been noted in a substantial minority or survivors. The cause of the neurologic abnormalities remains uncertain but may be at least in part related to the pre-existing respiratory failure, as has been suggested in studies of ECMO survivors from other centers. In the proposed research, we plan to systematically and prospectively study all infants who are considered possible candidates for ECMO therapy. The temporal relationship of brain electrical, neurosonographic and cerebrovascular abnormalities to respiratory disease and its treatment will be determined by serially repeating EEG, cranial ultrasound and color Doppler imaging studies during and following ECMO or conventional ventilator therapy. Prenatal, intrapartum, and neonatal data will be analyzed and follow-up studies are planned to evaluate the developmental status of all survivors. The purpose of the research is to determine the etiology of the neurologic damage observed in many ECMO survivors. Our long range goals are to develop treatment methods that will prevent brain damage in neonatal infants who are susceptible to hypoxemia from severe respiratory failure.